Concept Guide

CONFIGURATION mode
ip extcommunity-list extcommunity-list-name
2. Two types of extended communities are supported.
CONFIG-COMMUNITY-LIST mode
{permit | deny} {{rt | soo} {ASN:NN | IPADDR:N} | regex REGEX-LINE}
Filter routes based on the type of extended communities they carry using one of the following keywords:
● rt: route target.
● soo: route origin or site-of-origin. Support for matching extended communities against regular expression is also
supported. Match against a regular expression using the following keyword.
● regexp: regular expression.
To set or modify an extended community attribute, use the set extcommunity {rt | soo} {ASN:NN | IPADDR:NN}
command.
To view the configuration, use the show config command in CONFIGURATION COMMUNITY-LIST or CONFIGURATION
EXTCOMMUNITY LIST mode or the show ip {community-lists | extcommunity-list} command in EXEC Privilege
mode.
DellEMC#show ip community-lists
ip community-list standard 1
deny 701:20
deny 702:20
deny 703:20
deny 704:20
deny 705:20
deny 14551:20
deny 701:112
deny 702:112
deny 703:112
deny 704:112
deny 705:112
deny 14551:112
deny 701:667
deny 702:667
deny 703:667
deny 704:666
deny 705:666
deny 14551:666
DellEMC#
Configure BGP attributes
Following sections explain how to configure the BGP attributes such as MED, COMMUNITY, WEIGHT, and
LOCAL_PREFERENCE.
Changing MED Attributes
By default, Dell EMC Networking OS uses the MULTI_EXIT_DISC or MED attribute when comparing EBGP paths received from
different BGP neighbors or peers from the same AS for the same route. You can configure the device to compare the MED
attributes from neighbors or peers in different AS using the bgp always-compare-med command.
To change the usage of MED attribute to choose the best path among the advertised, enter any or all of the following
commands.
● Enable MED comparison in the paths from neighbors with different ASs.
CONFIG-ROUTER-BGP mode
bgp always-compare-med
By default, this comparison is not performed.
● Change the bestpath MED selection.
CONFIG-ROUTER-BGP mode
bgp bestpath med {confed | missing-as-best}
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Border Gateway Protocol (BGP)